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XINGANG FU AND FEI HU
© 2010 Taylor & Francis Group, LLC
of the current Internet’s completely distributed hop-by-hop routing
architecture, which is lacking a solid centralized control of overall
network resources.
OpenFlow decouples the control and forwarding functionalities of
routing, in which the forwarding function stays within the OpenFlow
routers (forwarders), whereas the routing control function is handled
by a separate controller layer, which is the brain of the network and
could be centralized and/or possibly federated. Forwarding tables are
dynamically uploaded to forwarders by the controller layer. Figure 12.1
shows that the controller ...